• Korean Journal of Optics and Photonics
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• v.25 no.6
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• pp.334-339
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• 2014

In this paper, the optical properties of a miniature telecentric camera are studied analytically and experimentally. By means of optical properties, the luminous intensity of retro-reflection of a miniature telecentric optical system is investigated. First, from a simulation the theoretical value of the coefficient of luminous intensity of retro-reflection of a miniature telecentric system is estimated. Second, a miniature telecentric camera device is designed, and the value of the coefficient of luminous intensity of retro-reflection of the actual device is measured through experiment. From simulation and experiment, we found that both the estimated and observed values of the coefficient of luminous intensity of retro-reflection range from 0.002 to $0.03m^2/sr$ (P384200CPH: $0.0042-0.018m^2/sr$, P285200CPH: $0.0045-0.0297m^2/sr$, P321450S: $0.0021-0.00963m^2/sr$) at 1.4 to 4.9 arcminute. The results prove the significance of the mechanisms used to design the miniature telecentric camera, and the experimental method. Accordingly, with these significant results, this study contributes to the development of theory and practice in optical engineering science.

• Progress in Medical Physics
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• v.27 no.2
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• pp.72-78
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• 2016

A CCD camera and an LED light source were combined to fabricate a compact optical CT scanner for the therapeutic radiation dose evaluation of a polymer gel dosimeter. After the collimated beam emitted by the LED passed through aquarium, gel phantom, and telecentric lens, an image was collected by the CCD camera and reconstructed using MATLAB. By using a stepping motor and LabVIEW, the gel dosimeter was rotated at every $0.72^{\circ}$, and the time for collecting 500 slice images per a revolution was within 20 min. At a spatial frequency of 4.5 lp/mm of the optical CT scanner, the modulation transfer function value was 72%. The linear correlation coefficient of the optical CT scanner for the polymer gel dosimeter was 0.987.

• Journal of Korean Ophthalmic Optics Society
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• v.7 no.2
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• pp.197-202
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• 2002

In this paper, we want to help understanding about telecentric as introducing the concept of the system and researching the optical properties after we choose the designed profile projection lens. An analyzed optical system is F-number=2.8 and the first lens is used negative lens. Accordingly, we can know this system is compacter, because the front focal position is to the inside of the system and aperture stop is designed to the inside of the optical system. The field is about $21^{\circ}$. Since the entrance pupil is located the front focal point, we can certify the exit pupil is -49404.1mm, located on the infinite toward the object space. Therefore, the optical system is the form of 'image space telecentricity'.